#region Copyright & License

//
// Copyright 2001-2005 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

#endregion

using System;
using System.IO;
using System.Text;

namespace log4net.Util {
  /// <summary>
  /// A <see cref="StringWriter"/> that can be <see cref="Reset"/> and reused
  /// </summary>
  /// <remarks>
  /// <para>
  /// A <see cref="StringWriter"/> that can be <see cref="Reset"/> and reused.
  /// This uses a single buffer for string operations.
  /// </para>
  /// </remarks>
  /// <author>Nicko Cadell</author>
  public class ReusableStringWriter : StringWriter {
    #region Constructor

    /// <summary>
    /// Create an instance of <see cref="ReusableStringWriter"/>
    /// </summary>
    /// <param name="formatProvider">the format provider to use</param>
    /// <remarks>
    /// <para>
    /// Create an instance of <see cref="ReusableStringWriter"/>
    /// </para>
    /// </remarks>
    public ReusableStringWriter(IFormatProvider formatProvider) : base(formatProvider) {}

    #endregion

    /// <summary>
    /// Override Dispose to prevent closing of writer
    /// </summary>
    /// <param name="disposing">flag</param>
    /// <remarks>
    /// <para>
    /// Override Dispose to prevent closing of writer
    /// </para>
    /// </remarks>
    protected override void Dispose(bool disposing) {
      // Do not close the writer
    }

    /// <summary>
    /// Reset this string writer so that it can be reused.
    /// </summary>
    /// <param name="maxCapacity">the maximum buffer capacity before it is trimmed</param>
    /// <param name="defaultSize">the default size to make the buffer</param>
    /// <remarks>
    /// <para>
    /// Reset this string writer so that it can be reused.
    /// The internal buffers are cleared and reset.
    /// </para>
    /// </remarks>
    public void Reset(int maxCapacity, int defaultSize) {
      // Reset working string buffer
      StringBuilder sb = GetStringBuilder();

      sb.Length = 0;

      // Check if over max size
      if (sb.Capacity > maxCapacity)
        sb.Capacity = defaultSize;
    }
  }
}